1.) Field of the Invention
The present invention relates to a method for collecting or storing objects in a warehouse, wherein an apparatus which is capable of movement along a rail is moved to a location where objects are to be collected or stored, which apparatus provides information with regard to the objects in question, wherein said rail is provided with electrical conductor means and wherein said apparatus is provided with contact elements, which are in contact with said conductor means, via which conductor means electric current is supplied to said apparatus for the drive unit which drives the apparatus.
2.) Description of the Prior Art
The collecting of objects from a warehouse can take place completely automatically, for example by means of robots, but it can also be carried out by warehouse employees, wherein each warehouse employee uses aids which enable him to perform his duties in an efficient manner. It is important that each employee receives clear-cut information in an efficient manner, that he can find the relevant space in the storage rack without difficulty, that he has his hands free as much as possible for picking up the objects in question, and furthermore it is important that the employee only needs to carry out a limited number of operations.
The apparatus, also called warehouse robot or rackrunner(copyright), rides on a rail with a number of wheels and stops at predetermined locations in order to supply the necessary information or carry out checks at said locations.
It is important that the apparatus is fed with the necessary data in a reliable manner during use. In PCT/NL95/00346 it is proposed to have the apparatus communicate with a central computer by transmitting data radiographically. In practice, however, this may lead to malfunction, since signals causing interference are produced in the surrounding area, or since the signals which provide the communication with the apparatus cause interference for other devices. It is partially for that reason that all kinds of regulations apply to the use of radiographic data transmission, which regulations vary per country. Accordingly, it is not possible to provide a system for universal usage.
It is, therefore, an objective of the present invention to provide a method wherein communication with the apparatus can take place in an effective and reliable manner, without any risk of interference of or by other systems and without special facilities on the apparatus being required.
In order to accomplish that objective, the apparatus is fed with data for providing the information via said conductor means and via said contact elements, which also supply the power for the drive unit of the apparatus. This implies that the same means are used for said power supply and for said communication, which leads to a simplification and to other advantages as referred to above. A modem in the apparatus and a modem in the central computer with which the apparatus communicates thereby carry out the conversion of data to be transmitted into signals which can be transferred via an electrical conductor. This equipment is simpler, cheaper and more reliable than transmitting equipment.
In one preferred embodiment, the apparatus not only receives data from a central computer via the conductor means and the contact elements, but it also transmits data to a central computer, that is, a processing and/or storage unit for said data, via said contact elements and said conductor means.
Preferably, the data are fed to the apparatus and transmitted by said apparatus during short interruptions of the power supply to the apparatus. This may for example take place in that means are present for interconnecting the two modems as soon as the power supply is temporarily interrupted. Said interruption will preferably take place when the apparatus is stationary for communication with operating staff.
In another preferred embodiment, the power supply to the apparatus is temporarily interrupted, for example for a fraction of a second, the moment data need to be transmitted. The transmitting modem can interrupt the current supply thereby, after which the receiving modem recognizes said interruption as a signal that data are about to be transmitted. Said interruption is so short that it does not interfere with the operation of the apparatus. Preferably, the apparatus comprises a rechargeable battery, which ensures a constant power supply to the apparatus, also during interruptions in the power supply.
In another preferred embodiment, the data are fed to the apparatus and transmitted by the apparatus while power is being supplied to the drive unit, to which end the voltage of the current is modulated. The voltage is imparted a small fluctuation thereby, which is produced by a modem and which can subsequently be converted again into transmitted information by another modem.
The invention furthermore relates to a device for collecting or storing objects in a warehouse, which device comprises an apparatus which is capable of indicating how many objects are to be collected or stored at a particular location and/or which converts data into visible or audible information, and which comprises a rail along which said apparatus can be moved, which rail is provided with electrical conductor means, and which apparatus is provided with contact elements, which are in contact with said conductor means, via which conductor means and contact elements electric power can be supplied to the apparatus for the drive unit which drives the apparatus, which device comprises means for supplying said apparatus with data, via said conductor means and said contact elements, for providing said information.
Preferably, said contact elements are sliding contacts, which are capable of sliding over the conductor means present in the rail, and in another preferred embodiment said contact elements comprise wheels which are capable of rolling on the conductor means present in the rail. Both possibilities are well-tested means for transferring electrical signals. Preferably, the same sliding contacts or wheels are used for supplying power to the drive unit of the apparatus.
The apparatus is preferably provided with a keypad and/or a display and/or a printer and/or a loudspeaker and/or an indicator which is capable of referring to a space in the warehouse and/or a pilot light and/or a carrying handle and/or a scanner which is capable of reading a bar code on the rail and/or a signal port for a manually operated scanner and/or a fixed bar code scanner for recognizing objects.
In one preferred embodiment, the apparatus comprises a weighing device for weighing goods at the location where they are stored. Such a mobile weighing device may also be considered to constitute a separate invention.
Preferably, a conveyor is furthermore provided, which can be moved to the location where the apparatus is present, whereby a wireless exchange of data takes place between the apparatus and the conveyor by means of infrared or ultrasonic signals. Such wireless transmission of data is known per se. In another embodiment, a warehouse employee can communicate with the apparatus by means of a keypad and/or a display, which is disposed remote from the apparatus, for example on the conveyor, wherein the data are transmitted by means of infrared or ultrasonic signals.